The proliferation and increased usage of portable computer and electronic devices has greatly increased demand for memory cells. Digital cameras, digital audio players, personal digital assistants, and other electronic devices generally seek to employ large capacity memory cells (e.g., flash memory, smart media, compact flash, or the like). Such memory cells can be typically employed in various types of storage devices.
Generally, information is stored and maintained in one or more of a number of types of storage devices. Storage devices include long term storage mediums such as, for example, hard disk drives, compact disk drives and corresponding media, digital video disk (DVD) drives, and the like. The long term storage mediums typically store larger amounts of information at a lower cost, but are slower than other types of storage devices. Storage devices also include memory devices, which are often, but not always, short term storage mediums. Memory devices tend to be substantially faster than long term storage mediums.
Such memory devices include, for example, dynamic random access memory (DRAM), static random access memory (SRAM), double data rate memory (DDR), flash memory, read only memory (ROM), and the like. Memory devices are subdivided into volatile and non-volatile types. Volatile memory devices generally lose their information if they lose power and typically require periodic refresh cycles to maintain their information. Volatile memory devices include, for example, random access memory (RAM), DRAM, SRAM and the like. Non-volatile memory devices maintain their information whether or not power is maintained to the devices. Non-volatile memory devices include, but are not limited to, ROM, programmable read only memory (PROM), erasable programmable read only memory (EPROM), flash memory and the like. Volatile memory devices generally provide faster operation at a lower cost as compared to non-volatile memory devices.
Accordingly, each memory cell in a memory device can be accessed or “read”, “written”, and “erased” with information. The memory cells maintain information in an “off” or an “on” state (e.g., are limited to 2 states), also referred to as “0” and “1”. Typically, a memory device is addressed to retrieve a specified number of byte(s) (e.g., 8 memory cells per byte). Typically, for volatile memory devices, the memory cells must be periodically “refreshed” in order to maintain their state. Such memory devices are usually fabricated from semiconductor devices that perform these various functions and are capable of switching and maintaining the two states. The devices are often fabricated with inorganic solid state technology, such as, crystalline silicon devices.
Because of the increasing demand for information storage, memory device developers and manufacturers are constantly attempting to increase speed and storage retrieval for memory devices (e.g., increase write/read speed). Nonetheless, in general for such memory cells a programming threshold for operation is fixed, and the circuits are being designed around such permanent and unchanging values. At the same time, silicon-based devices are approaching their fundamental physical size limits. Moreover, inorganic solid state devices are generally encumbered with a complex architecture which leads to high cost and a loss of data storage density. Therefore, there is a need to overcome the aforementioned deficiencies associated with conventional systems